ArUco Marker detection: unable to grab any frame

[k211]

System information (version)

• OpenCV => 4.6.0
• Operating System / Platform => Ubuntu 20.04
• Compiler => Cmake

Detailed description

Hello, I am currently trying to do ArUco marker detection using the code from https://github.com/opencv/opencv_contrib/blob/4.x/modules/aruco/samples/detect_markers.cpp (only copy and paste). However, Some problems occured when I pass the input video/image to the code.

To be more specific, when I connect the webcam, it says "camera index out of range" ; when I input a video (.mov file and .webm file), it says "can't find starting number", and when I input an image (.jpeg file), there is no error, but the "inputvideo.grab"= 0, which means it can't grab and frames. I think the "inputvideo.grab=0" problem is the most urgent one, because whether the input is an image or video or webcam, no frame can be grabbed. Have you met any of these problems before? Thanks!